1. Field of the Invention
This invention relates to a fan assembly for automotive vehicles and more particularly to a bushing through which a bolt for connecting the fan assembly to an output member of internal combustion engine is passed.
2. Description of the Prior Art
Conventionally, the fan assembly has been used for cooling a radiator in an automotive vehicle. The fan assembly includes a hub portion including a stem extending radially inwardly therefrom and blades extending radially outwardly therefrom. The hub portion of the fan assembly is made of molded plastic for simplicity of manufacturing and prevention of noise occasionally produced by metal blades.
The stem of the hub portion is circumferentially provided with a plurality of holes, each hole being inserted with the bushing through which the bolt is passed for connecting the fan assembly to, for instance, the output shaft of the fluid coupling. However, the stem is subject to deformation due to the environmental temperature-variation therearound with the result that loosening of the connection between the stem and the bushing is caused. Therefore, it is hard to transmit the engine-torque from the output shaft of the fluid coupling to the stem of fan assembly without any loss thereof.
On the other hand, in some kinds of fan assemblies a spacer is additionally interposed between the stem and a flange of the bushing to thereby improve such torque transmission. But, since it is also hard to fix the spacer and the bushing with each other, the engine-torque will not be effectively transmitted to the fan assembly.